#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
using namespace std;

const ll N = 1e6 + 10, INF = 0x3f3f3f3f;

ll n;

ll val(ll i, ll j) { return (i - 1) * n + j; }

void solve()
{
    ll ans = 0;
    cin >> n;
    if (n % 2 == 0) {
        for (ll i = 1;i <= n;i += 2)
            ans += val(i, i) + val(i, i + 1) + val(i + 1, i) + val(i + 1, i + 1);
    } else {
        for (ll i = 1;i <= n - 3;i += 2)
            ans +=  val(i, i) + val(i, i + 1) + val(i + 1, i) + val(i + 1, i + 1);
        ans += val(n - 2, n - 2) + val(n - 2, n - 1);
        ans += val(n - 1, n - 1) + val(n - 1, n);
        ans += val(n, n - 2) + val(n, n);
    }
    cout << ans << '\n';
}

signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
    std::istringstream in(R"()");
    std::cin.rdbuf(in.rdbuf());
#endif
    ll T = 1;
    //cin>>T;
    for (ll i = 1;i <= T;i++) {
        solve();
    }
}